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National 5 Biology > Whole Course > Flashcards

Whole Course Flashcards

Made From Notes at: http://www.duncanrig.s-lanark.sch.uk/wp-content/uploads/National-5-Full-Course-Glossary.pdf

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AP® Biology flashcards Biology 101 flashcards
1
Q

Mitochondria

A

The site of aerobic respiration

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2
Q

Chloroplasts

A

The site of photosynthesis in a plant cell

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3
Q

cell membrane

A

Controls the entry and exit of materials

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4
Q

vacuole

A

A large, cell sap-filled space in plant cells

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5
Q

nucleus

A

Contains DNA and controls all cell activities

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6
Q

cytoplasm

A

Site of chemical reactions

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7
Q

ribosomes

A

The site of protein synthesis

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8
Q

plasmids

A

Small circular pieces of DNA in bacterial cells

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9
Q

Cell walls

A

Provides cell with shape and support. Made of cellulose in plant cells and different materials in bacteria and
fungi

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10
Q

The cell membrane consists of

A

phospholipids and proteins

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11
Q

The cell membrane is

A

selectively permeable

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12
Q

passive transport is

A

Down the concentration gradient and does not require energy.

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13
Q

diffusion in cells is

A

The movement of molecules down a concentration gradient

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14
Q

Osmosis is

A

The movement of water molecules from a high water concentration to a low water concentration through a
selectively permeable membrane

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15
Q

Animal cells in low water concentration will

A

Shrink

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16
Q

Animal cells in high water concentration will

A

Burst

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17
Q

Plant cells in low water concentration will

A

Become plasmolysed- vacuole shrinks and cytoplasm pulls away from cell wall

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18
Q

Plant cells in high water concentration will become

A

Become turgid- swollen

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19
Q

Active transport

A

Requires energy for membrane proteins to move molecules and ions against the concentration gradient

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20
Q

DNA carries

A

The genetic information for making proteins

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21
Q

A DNA molecules is

A

A double-stranded helix

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22
Q

A gene is

A

A section of DNA which codes for a particular protein

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23
Q

DNA double strands are held together by

A

Complementary base pairs

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24
Q

The four bases in the genetic code are

A

Adenine, cytosine, guanine and thymine (A,T,C,G)

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25
Q

The base sequence determines

A

The amino acid sequence in a protein

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26
Q

mRNA carries

A

A complementary copy of the code from the DNA, in the nucleus, to a ribosome

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27
Q

The ribosome is where

A

The protein is assembled from amino acids

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28
Q

The sequence of amino acids

A

Controls the shape and function of proteins

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29
Q

Structural proteins

A

Hold tissues together e.g. collagen

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30
Q

Hormones

A

Are chemical messengers which carry a message from a gland to a receptor via the blood

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31
Q

Antibodies

A

Are proteins, made by white blood cells, which bind to invading microbes

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32
Q

Receptors

A

Receive a signal from the environment and pass it on to a sensory neuron OR bind to a hormone and tell the cell
what to do.

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33
Q

Enzymes

A

Are biological catalysts and are made by all cells

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34
Q

Biological catalysts

A

Speed up biochemical reactions in cells and remain unchanged in the process

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35
Q

Enzyme specificity

A

One enzyme will only catalyse one reaction

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36
Q

Active site

A

The part of the enzyme that the substrate attaches to

and is a complementary shape to it

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37
Q

Substrate

A 
The reactant(s) in a reaction, and is specific to an
enzyme
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38
Q

Product

A

The molecule made by an enzyme-controlled reaction

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39
Q

Denatured

A

When the active site permanently changes shape and affects the rate of the enzyme reaction

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40
Q

Optimum conditions

A

Are the temperature and pH which the enzymes work best at

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41
Q

Finished the sentences on the process of genetic engineering.

  1. Identify the section of DNA that has
  2. Then you need to
  3. And
  4. Then insert
  5. Then insert
    Then the transformed cells need to
A
  1. Identify the section of DNA that has the gene required, on the source chromosome
  2. Then you need to extract (cut out) the gene
  3. And extract the plasmid from the vector/bacterial cell
  4. Then insert the cut out gene into a bacterial plasmid
  5. Then insert the plasmid into the host cell (bacteria)
    Then the transformed cells need to grow and divide to produce a GM organism
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42
Q

Enzymes are needed to

A

Cut the DNA to extract the gene, cut the plasmid open and seal the gene into the plasmid

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43
Q

Respiration is defined as

A

A series of enzyme-controlled reactions which release the chemical energy stored in glucose

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44
Q

The energy released from respiration is used to make

A

ATP from ADP and Pi

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45
Q

The chemical energy in ATP can be released by

A

Breaking it down into ADP and Pi

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46
Q

The released energy from respiration can be used for

A

muscle cell contraction, cell division, protein synthesis, transmission of nerve impulses

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47
Q

Stage one of respiration breaks one molecule of glucose down into

A

2 molecules of pyruvate and releases enough energy to make 2 ATP molecules

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48
Q

Stage 2 of respiration with oxygen (aerobic respiration) breaks pyruvate down into

A

Carbon dioxide and water and yields 36 ATP molecules

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49
Q

Stage 2 of respiration without oxygen is called

A

Fermentation and yields 0 ATP molecules

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50
Q

The end product of fermentation in animal cells is

A

Lactate

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51
Q

The end products of fermentation in plant and yeast cells are

A

Ethanol + carbon dioxide

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52
Q

Total ATP yield of aerobic respiration

A

38 ATP molecules

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53
Q

Total ATP yield of fermentation

A

2 ATP molecules (only those produced in stage 1)

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54
Q

Respiration begins in

A

The cytoplasm

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55
Q

Fermentation is completed in

A

The cytoplasm

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56
Q

Aerobic respiration is completed in

A

The mitochondria

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57
Q

Respirometers

A

Measure the rate of respiration

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58
Q

Mitosis is

A

Normal cell division and provides new cells for growth and repair of damaged cells and maintains the diploid
chromosome complement

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59
Q

Chromatids are

A

Individual strands of a duplicated chromosome (joined together at centromere)

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60
Q

The equator

A

Is the middle of the cell where the chromosomes (pairs of chromatids) line up

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61
Q

Spindle fibres are

A

Where chromosomes attach to by the centromere; they contract to pull the chromatids apart to the poles

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62
Q

Stem cells are

A

Unspecialised cells which can divide in order to self- renew or differentiate (specialise) to become specialised cells

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63
Q

Stem cells are normally involved in

A

Growth and repair

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64
Q

Specialisation leads to the formation of

A

A variety of cells, tissues and organs

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65
Q

Groups of organs working together to perform a particular function is called an

A

Organ system

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66
Q

The hierarchy of organisation of living organisms is

A

Cells-tissues-organs-organ systems-organism

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67
Q

The central nervous system (CNS) consists of

A

The brain and the spinal cord

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68
Q

The brain contains

A

The cerebrum, cerebellum and medulla

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69
Q

The cerebrum controls

A

Conscious thought, intelligence, language

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70
Q

The cerebellum controls

A

Balance and co-ordination

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71
Q

The medulla controls

A

Unconscious control of body temp, heart and breathing rate, etc.

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72
Q

Neuron types are

A

Sensory, Inter and motor

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73
Q

Reflex actions are

A

Involuntary protective actions

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74
Q

The reflex arc is

A

Receptor – sensory neuron – relay neuron – motor neuron – muscle

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75
Q

Receptors

A

Detect stimuli / sensory information

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76
Q

Electrical impulses

A

Carry messages along neurons

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77
Q

Synapses

A

Gaps between neurons that the message has to cross via chemical messenge

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78
Q

Hormones are

A

Chemical messengers produced by endocrine glands which carry messages in the blood stream to target
tissues

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79
Q

Target tissues have cells with

A

Receptor proteins that are complementary to a specific hormone, so only that tissue will be affected by
that hormone

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80
Q

Blood glucose levels need to be

A

Controlled within safe limits (not too high and not too low)

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81
Q

Insulin is released when

A

The blood sugar rises above normal

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82
Q

Insulin causes

A

Liver cells to store excess glucose as glycogen returning blood glucose levels to normal

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83
Q

Glucagon is released when

A

The blood sugar falls lower than normal

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84
Q

Glucagon causes

A

Liver cells to release glucose into the blood returning blood glucose levels to normal

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85
Q

The pancreas

A

Is the endocrine gland which produces insulin and glucagon

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86
Q

All body cells, except gametes, are

A

Diploid

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87
Q

Gametes are

A

Haploid sex cells

88
Q

Diploid means

A

The normal number of chromosomes in a cell. In humans this is 23 pairs (46).

89
Q

Haploid means

A

Half the normal number of chromosomes in a cell. In humans this is 23.

90
Q

Gametes have

A

Only one of each pair of chromosomes normally present in a diploid cell

91
Q

Male gametes are made in

A

Testes (animals)/ anthers (plants)

92
Q

Male gametes are called

A

Sperm (animals) / pollen (plants)

93
Q

Female gametes are made in

A

Ovaries (animals)/ ovaries (Plants)

94
Q

Female gametes are called

A

Eggs (animals) / ovules (plants)

95
Q

Fertilisation is

A

The fusion of two haploid gametes to forma diploid zygote which undergoes many cell divisions to form an
embryo

96
Q

Discrete variation (single gene inheritance)

A

Discontinuous, where the values do not occur in a range and fall into distinct groups (usually descriptions
e.g. colour)

97
Q

Continuous variation (polygenic inheritance)

A

Where there is a range of values on a scale e.g. height

98
Q

Polygenic characteristics

A

Caused by many genes working together. They show continuous variation and very common in phenotypes.

99
Q

Phenotype

A

The visible physical characteristic you see as a result of a gene

100
Q

Gene

A

A section of DNA which codes for a protein (characteristic)

101
Q

Alleles

A

Different forms of a gene which control one characteristic

102
Q

Genotype

A

The pair of alleles a person has which control one characteristic, e.g. AA, aa or Aa

103
Q

Dominant

A

An allele which is always seen in the phenotype if it is present (in the genotype)

104
Q

Recessive

A

An allele which is only seen in the phenotype if there is no dominant allele present

105
Q

Homozygous

A

When a genotype has two alleles exactly the same, e.g. AA or aa

106
Q

Heterozygous

A

When a genotype has alleles which are different from each other e.g. Aa

107
Q

P1

F1 (first filial generation) F2 (second filial generation)

A

P1 -The genotypes of the parents in a cross
F1 (first filial generation) -The genotypes of the offspring from a cross
F2 (second filial generation)-The genotypes of the offspring resulting if two of the original F1 offspring were crossed

108
Q

Predicted ratios are not always achieved

A

Because fertilisation is a random process or sample size is too small

109
Q

Plant organs are

A

Roots, leaves and stems

110
Q

Plants need water for

A

Transporting materials and for photosynthesis

111
Q

Leaf cells, from top to bottom are

A

Upper epidermis, palisade mesophyll, spongy mesophyll, vein (consisting of xylem and phloem),
lower epidermis, guard cells, (stomata)

112
Q

Root hair cells have a

A

Large surface area to increase absorption of water from the soil

113
Q

Xylem vessels are

A

Dead and contain spirals of lignin for support

114
Q

Xylem vessels transport

A

Water and minerals up the stem

115
Q

The evaporation of water through leaves is called

A

Transpiration

116
Q

Guard cells control

A

The opening and closing of stomata (turgid/swollen guard cells= open stomata)

117
Q

The epidermis

A

Covers the upper and lower surfaces of a leaf transparent to let light through to photosynthetic layers

118
Q

Phloem transports sugar and is made of

A

Living cells consisting of cytoplasmic strands and porous end plates between cells that allow sugar to move from
cell to cell. Companion cells provide energy for sieve tubes

119
Q

In mammals, the substances transported by the blood are

A

Nutrients (glucose and amino acids), oxygen and carbon dioxide

120
Q

In mammals, blood contains

A

Plasma, red blood cells and white blood cells

121
Q

Red blood cells are specialised to transport oxygen by

A

Being biconcave in shape to increase surface area for absorption/diffusion of oxygen
Having no nucleus so more space for haemoglobin
Containing haemoglobin which bind to oxygen to transport it

122
Q

When oxygen binds to haemoglobin in red blood cells it is called

A

oxyhaemoglobin

123
Q

White blood cells are part of

A

The immune system and are involved in destroying pathogens (foreign organisms)

124
Q

White blood cells called Lymphocytes produce

A

Antibodies which destroy pathogens

125
Q

Antibodies are

A

Specific to a particular pathogen

126
Q

The heart has four chambers.
The top two are:
The bottom two are:

A

The top two are: Right and left atria

The bottom two are: Right and left ventricles

127
Q

White blood cells called phagocytes carry out

A

Phagocytosis to engulf and destroy pathogens

128
Q

The heart contains valves which are found

A

Between the atria and ventricles and between the ventricles and arteries

129
Q

Valves

A

Prevent the backflow of blood

130
Q

Veins carry blood

A

Back to the heart, into the atria

131
Q

The pathway of blood through the heart, lungs and body is; beginning with the lungs:

A

Lungs (oxygenated) – pulmonary vein – left atrium – valve – left ventricle – valve – aorta – body cells

(deoxygenated) – vena cava – right atrium – valve – right ventricle – valve – pulmonary artery – lungs

132
Q

Arteries carry blood under

A

High pressure

133
Q

The structures of arteries which help them to do this are

A

1 thick muscular walls

2 narrow central channel (lumen)

134
Q

Veins carry blood under

A

Low pressure

135
Q

The structures of veins which help them to do this are

A

1 Thinner walls
2 wide central channel (lumen)
3 valves to prevent backflow of blood

136
Q

Capillaries are found in

A

Organs and tissues as networks

137
Q

Capillaries are where

A

Exchange of materials happens, e.g. glucose, carbon dioxide, oxygen, urea, by diffusion

138
Q

Capillaries are adapted for this by

A

1 having a large surface area for diffusion

2 having very thin walls – one cell thick

139
Q

Oxygen and nutrients from food must be absorbed into the bloodstream and delivered to cells for

A

respiration

140
Q

Waste materials must be removed from cells into the bloodstream. Waste materials include

A

Carbon dioxide

141
Q

Surfaced involved in the absorption of materials have these features in common

A

Large surface area
Thin walls
Extensive blood supply

142
Q

Large surface area, Thin walls,Extensive blood supply during absorption

A

Increase efficiency of absorption

143
Q

Tissues contain capillary networks to allow

A

Exchange of materials at cellular level

144
Q

Gas exchange in the lungs happens in the

A

Alveoli

145
Q

In alveoli, the direction of gas movement is

A

Oxygen in, carbon dioxide out

146
Q

The gases are exchanged from

A

The blood capillaries surrounding the alveoli

147
Q

alveoli are adapted for diffusion by

A

1 having a large surface area (there are many of them) 2 having a good blood supply (covered by capillary
networks)
3 having thin walls (one cell thick) for more efficient diffusion

148
Q

The small intestine is where

A

Absorption of food happens

149
Q

The small intestine contains many millions of

A

Villi

150
Q

Villi are

A
  1. thin walled
  2. have a large surface area (there are many of them)
  3. have a good blood supply to aid absorption- each villus contains a network of capillaries)
151
Q

Water soluble food products are

A

Glucose and amino acids

152
Q

They are absorbed into the

A

Blood capillary

153
Q

Fat soluble food products are

A

Fatty acids and glycerol

154
Q

They are absorbed into

A

The central lacteal

155
Q

Biodiversity is

A

All the organisms of one species in a habitat

156
Q

Population

A

All the organisms of one species in a habitat

157
Q

Community

A

All the living organisms living in a habitat

158
Q

An ecosystem is

A

All the organisms (community) living in a habitat and the non-living components with which the organisms interact (the abiotic factors)

159
Q

Consumer

A

Organisms which rely on eating other organisms for food

160
Q

Carnivore

A

A meat-eater

161
Q

Herbivore

A

A plant-eater

162
Q

Omnivore

A

An organism which eats both plants and animals

163
Q

Food chain

A

Shows the transfer of energy between organisms

164
Q

Between levels in a food chain, 90% energy is

A

Lost as heat, movement or undigested materials

165
Q

A niche is

A

The role that an organism plays within a community

166
Q

A niche describes:

A

The resources the organism uses in an ecosystem (light, temperature, nutrient availability)
The interactions and organism has in the community (competition, parasitism, predation)

167
Q

Competition between organisms in ecosystems occurs when

A

Resources are in short supply

168
Q

Interspecific competition is

A

between members of different species competing for one or a few similar resources the require

169
Q

Intraspecific competition is

A

Between members of the same species competing for all the same resources they require and is therefore much
more intense that interspecific

170
Q

Biotic factors are

A

Living e.g competition, disease, food availability, grazing, predation

171
Q

Abiotic factors are

A

non-living, e.g. temperature, pH, light intensity, moisture

172
Q

Sampling is used to

A

estimate the size of a population of an organism in a habitat or ecosystem.

173
Q

Sampling plants and animals: techniques include

A

Quadrats or pitfall traps, plus transect, Tullgren funnel, pooters, tree beating, sweep net, pond netting

174
Q

Equipment required to measure abiotic factors include

A

Light meters, moisture meters, pH meters and thermometers

175
Q

All sampling and measuring techniques need to be evaluated for

A

Limitations and sources of error

176
Q

Paired statement and branched keys can be used to

A

Identify organisms

177
Q

Indicator species are species that

A

By their presence or absence indicate environmental quality/levels of pollution

e. g. lichen
e. g. freshwater invertebrates

178
Q

Photosynthesis has two stages called

A

Light reactions and carbon fixation

179
Q

Light reactions need

A

light energy from the sun, and water

180
Q

Light energy from the sun is

A

trapped by chlorophyll in the chloroplasts and is converted into chemical energy and used to generate ATP

181
Q

Water is

A

Split to produce hydrogen and oxygen.

182
Q

Hydrogen

A

Is used in stage 2

183
Q

Oxygen then

A

Diffuses out of the cell as a by-product

184
Q

Carbon fixation needs

A

Hydrogen, ATP and carbon dioxide

185
Q

A series of enzyme-controlled reactions produces

A

Sugar

186
Q

The Sugar produced in photosynthesis can be used for

A

Respiration (glucose), making starch for storage or cellulose for structural uses.

187
Q

Limiting factors are factors that

A

If in short supply will limit the rate of photosynthesis and plant growth

188
Q

Examples of limiting factors are

A

CO2 concentration, light intensity and temperature

189
Q

Between levels in a food chain, 90% energy is

A

Lost as heat, movement or undigested materials

190
Q

Only a small quantity is used for

A

growth and is therefore available at the next level of a food chain

191
Q

A pyramid of numbers is

A

A diagram which shows the relative total number of organisms present at each stage in the food chain.

192
Q

A pyramid of energy is

A

a diagram which shows the total energy of organisms present at each stage in the food chain.

193
Q

Unusual pyramids (non-pyramidal) of numbers exist when

A

The producer is a single organism (a tree)

194
Q

Increasing human population requir

A

Increased food yield

195
Q

This can include the use of

A

Fertilisers and pesticides

196
Q

Fertilisers increase the

A

nutrient content of soil to improve plant growth and crop yield

197
Q

Nitrates dissolved in soil water are absorbed by plants via roots and are used to make

A

Amino acids which are used to build Proteins

198
Q

Fertilisers can leach into fresh water causing

A

Algal blooms

199
Q

Algal blooms lead to

A

A reduction in light levels, killing aquatic plants

200
Q

Dead plants and dead algae

A

Become food for bacteria, which increase greatly in number

201
Q

The bacteria

A

Use up large quantities of oxygen, reducing availability for other organisms

202
Q

Pesticides are used to

A

Kill plants and animals that reduce crop yield

203
Q

Pesticides sprayed onto crops can

A

Accumulate in the bodies of organisms over time (bioaccumulation)

204
Q

Pesticides are passed along food chains and

A

Toxicity increases and can reach lethal levels

205
Q

Biological control may be

A

An alternative to pesticides (e.g. ladybirds controlling greenfly populations)

206
Q

GM crops may be

A

An alternative to fertiliser use (e.g. increased yield varieties)

207
Q

A mutation is

A

A random change to genetic material: the only source of new alleles

208
Q

Mutations may be

A

Radiation and some chemicals

209
Q

Environmental factors which increase the rate of mutation are

A

Radiation and some chemicals

210
Q

New alleles results in increased

A

Variation (differences) between members of a species

211
Q

Variation within a population makes it possible for a population to

A

Evolve over time in response to changing environmental conditions

212
Q

Natural selection is also called

A

Survival of the fittest

213
Q

Natural selection occurs when:

A
  1. More offspring are produced than the environment can sustain
  2. There are selection pressures
  3. Only the best adapted individuals (those with
    selective advantage) survive and breed
  4. They pass on their advantageous alleles and
    these alleles increase in frequency within the poulation
214
Q

Speciation occurs when:

A
  1. Part of a population becomes isolated by an isolation barrier
  2. Mutations occur in each sub-population
  3. natural selection follows selects for different
    mutations in each group due to different
    selection pressures
  4. each sub-population evolves until they become
    so genetically different that they are now two
    different species.
  5. Members from each group can no longer
    interbreed to produce fertile offspring
215
Q

Isolating barriers can be

A

Geographical, ecological or reproductive

National 5 Biology (4 decks)

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